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Radiator Leak?

my car started leaking fluid and can’t find the leak.
radiator is too hot to open to look, any thoughts?
it’s a 2007 ford van, with 133,000 miles on it
mechanic looked at engine and could find no leak - what to do?

For safety, DO NOT remove the radiator cap from a hot engine. Let it cool completely first.

The right way to search for such a leak is with a pressure test. Sometimes it’s hard to create the conditions for the leak by driving, but it’s usually easy with a pressure tester. There’s a test device that some auto parts stores have in their tool loan program, Autozone is one such place. The test is simple enough, you could do it yourself if you care to. Chances are your mechanic has one. Park the car at night, do the test the following morning. Bring a good bright flashlight. You remove the cap, attach the pressure pump, and pump to the pressure specified on your radiator cap (but be sure it’s the correct cap for your van…don’t over pressurize). If the gauge on the tester shows pressure drop, then look carefully at all hoses, radiator, and elsewhere for the origin of the leaking water. Hopefully it will be just a hose clamp that needs to be tightened, or a hose that needs to be replaced. A water pump is another possibility, as well as the heater core.

Regardless, your coolant may be due for replacement, and even if you solve the leak easily, you should probably replace the coolant if it hasn’t been done in a while - see your owner’s manual for specific information on that. All hoses should be replaced periodically too, you may be due for that also…an ounce of prevention is worth a pound of cure.

thankyou - hadn’t thought of heater core. will check!

Chances are that the heater core would leak into the cabin, not on the ground, and you’d notice a smell probably before you saw a leak.

How do you know it’s leaking?
Does it drip or you just notice the fluid level dropping?

Why do you think it is radiator fluid that is leaking? You mean from the appearance and water-like consistency of the pool of fluid on the ground you think it is radiator fluid (engine coolant)?

Coolant can leak from dozens of places in a car’s engine compartment. The most common is the water pump and the radiator. Either can easily spring a leak. And at 133k, that wouldn’t be unusual for either location. If the engine has recently overheated, it is probably the radiator. If not, it is probably the water pump. Also, it is entirely possible the coolant was simply over-filled recently, and there’s really nothing wrong at all. A leak cannot be denied, if there’s something leaking on the cement. And it should be relatively straight forward to determine where the leak is originating at that time. You’ll have to have a mechanic do a visual check at the time it is leaking.